1.
What is the name of the process that joins monomers together to make polymers?
Correct Answer
E. Dehydration synthesis
Explanation
Dehydration synthesis is the correct answer because it refers to the process of joining monomers together to form polymers by removing a water molecule. This process involves the bonding of monomers through a chemical reaction, resulting in the formation of larger molecules with the elimination of water.
2.
In hydrolysis, __________________ , and in this process water is _________________________ .
Correct Answer
A. A polymer breaks up to form monomers ... consumed
Explanation
In hydrolysis, a polymer breaks up to form monomers. This process requires the consumption of water.
3.
In science knowing Latin and Greek roots is frequently helpful in understanding definitions. One example is hydrolysis because hydro- refers to water and -lysis means __________________ which is literally what happens during the process of hydrolysis.
Correct Answer
break
breaking
break using
Explanation
The correct answer is "break". In the process of hydrolysis, a compound is broken down into smaller molecules or ions by the addition of water. The root "hydro-" refers to water, and "-lysis" means break down or decomposition. Therefore, "break" is the appropriate term to describe what happens during hydrolysis.
4.
Figure 5.15 in your textbook shows 8 of the possible functions of proteins in living things. In each of the 8 smaller pictures (except structural proteins), the proteins are shown in the color _________________________.
Correct Answer
purple
violet
Explanation
The correct answer is purple and violet. In Figure 5.15 of the textbook, the 8 possible functions of proteins in living things are depicted. In each of the smaller pictures, except for structural proteins, the proteins are shown in the color purple or violet.
5.
Check any of the following that are possible functions of proteins. Consult Fig. 5.15 in your text for help.
Correct Answer(s)
A. Transporting substances in/out of cells.
B. As a support protein in hair, feathers, connective tissues, etc.
C. As hormones that cause other tissues to respond.
E. As enzymes that speed up chemical reactions.
Explanation
Proteins have various functions in the body, including transporting substances in and out of cells, providing support in tissues such as hair, feathers, and connective tissues, acting as hormones to regulate other tissues, and functioning as enzymes to accelerate chemical reactions. These functions are essential for the proper functioning of cells and the overall functioning of the organism.
6.
The major parts of an amino acid are a central Carbon atom, an amino group, a carboxyl group, a single Hydrogen atom, and an R group which is identical in all 20 amino acids.
Correct Answer
B. False
Explanation
The statement is incorrect because the R group in an amino acid is not identical in all 20 amino acids. The R group, also known as the side chain, can vary in structure and composition, giving each amino acid its unique properties.
7.
According to Fig. 5.16 in your textbook, amino acids can be divided into 3 major categories based on their properties. These categories are _______________, polar, and electrically charged.
Correct Answer
nonpolar
hydrophobic
non-polar
non polar
Explanation
Amino acids can be divided into three major categories based on their properties: nonpolar, polar, and electrically charged. The correct answer options "nonpolar, hydrophobic, non-polar, non polar" all refer to the nonpolar category of amino acids. Nonpolar amino acids do not have a charge and are not attracted to water molecules, making them hydrophobic. The different variations in spelling ("nonpolar" vs "non-polar") do not affect the meaning in this context.
8.
Using Fig. 5.16 in your textbook you can see that molecules that are polar are also considered ______________________, or water loving.
Correct Answer
hydrophilic
Explanation
Using Fig. 5.16 in the textbook, it can be observed that polar molecules are classified as hydrophilic, which means they have an affinity for water. This implies that polar molecules are capable of forming hydrogen bonds with water molecules, making them soluble or easily dispersed in water. Therefore, the correct answer is hydrophilic.
9.
Every time a peptide bond is created to link 2 amino acids together a ______________ molecule is released. (See Fig. 5.17 for help)
Correct Answer
water
h2o
Explanation
When a peptide bond is formed between two amino acids, a water molecule is released as a byproduct. This process is known as dehydration synthesis or condensation reaction. The removal of a water molecule allows the amino acids to join together, forming a peptide bond. Therefore, the correct answer is water or H2O.
10.
In Fig. 5.17 in your textbook, how many amino acids are shown linked together in the molecule in the lower half of the diagram?
Correct Answer
C. 3
Explanation
In Fig. 5.17 in the textbook, the lower half of the diagram shows three amino acids linked together in the molecule.
11.
Every protein (polypeptide) has a free ________________ on one end and a free ___________________ on the other end.
Correct Answer
B. Amino group.....carboxyl group
Explanation
Proteins are made up of amino acids, which are connected by peptide bonds. The amino group (-NH2) of one amino acid forms a bond with the carboxyl group (-COOH) of another amino acid, resulting in the formation of a peptide bond. This process continues to form a polypeptide chain. Therefore, it is correct to say that every protein has a free amino group on one end (N-terminus) and a free carboxyl group on the other end (C-terminus).
12.
A polypeptide is the same as a protein.
Correct Answer
B. False
Explanation
A polypeptide is not the same as a protein. While a polypeptide is a chain of amino acids, a protein is a functional molecule that consists of one or more polypeptides. In other words, a polypeptide is a building block of a protein, but it does not possess the complex structure and functionality of a protein. Therefore, the given statement is false.
13.
On the bottom of p.80 your text states that, "a protein is not just a polypeptide chain". So what is a protein? Answers will NOT be counted correct unless they are in your own words - look on p.80 for this specific spot for the best answer.
14.
What determines the 3-D structure that a protein will have?
Correct Answer
C. The amino acid sequence of the protein
Explanation
The 3-D structure of a protein is determined by its amino acid sequence. The specific arrangement of amino acids in a protein chain determines how the protein folds and forms its unique structure. Different amino acids have different properties and interactions, such as hydrophobic or hydrophilic, that influence the folding process. These interactions between amino acids ultimately determine the final 3-D structure of the protein, including its secondary, tertiary, and quaternary structures. Therefore, the amino acid sequence is the primary factor that determines the 3-D structure of a protein.
15.
Fig. 5.18(a) shows the way that 1 polypeptide chain folds in 3-D space, but it also shows something else in yellow that helps the polypeptide keep its correct conformation. These yellow lines are:
Correct Answer
D. Disulfide bridges
Explanation
The correct answer is disulfide bridges. Disulfide bridges are covalent bonds formed between two cysteine residues in a polypeptide chain. These bridges play a crucial role in stabilizing the tertiary structure of proteins by creating strong connections between different parts of the chain. They help the polypeptide maintain its correct conformation in 3-D space, ensuring its proper folding and functionality.
16.
Explain what Fig. 5.19 is showing IN YOUR OWN WORDS.
17.
Which level of protein structure would describe a protein or polypeptide as having a-helices or b-pleated sheets?
Correct Answer
B. Secondary
Explanation
The secondary level of protein structure describes the protein or polypeptide as having α-helices or β-pleated sheets. This level of structure involves the folding of the polypeptide chain into regular patterns, such as helices or sheets, stabilized by hydrogen bonds between the backbone atoms. The primary structure refers to the linear sequence of amino acids, while the tertiary structure involves the overall 3D folding of the protein. The quaternary structure refers to the arrangement of multiple protein subunits.
18.
Which level of protein structure would tell you whether a protein is made of more than one polypeptide chain?
Correct Answer
D. Quaternary
Explanation
The quaternary level of protein structure refers to the arrangement of multiple polypeptide chains in a protein. It determines whether a protein is made up of more than one polypeptide chain. This level of structure is responsible for the overall shape and function of the protein, as the interactions between the different chains play a crucial role in its stability and activity.
19.
Which level of protein structure takes into account the total 3-D shape of a protein/polypeptide including its hydrophobic interactions which organize all hydrophobic R-group amino acids into the shielded center of the protein/polypeptide.
Correct Answer
C. Tertiary
Explanation
The tertiary level of protein structure takes into account the total 3-D shape of a protein/polypeptide including its hydrophobic interactions. Hydrophobic R-group amino acids are organized into the shielded center of the protein/polypeptide at this level.
20.
Which level of protein structure takes into account only the protein's simple sequence of amino acids?
Correct Answer
A. Primary
Explanation
The primary level of protein structure refers to the simple sequence of amino acids that make up the protein. It does not involve any folding or interactions between amino acids. This level is crucial because the specific sequence determines the protein's overall structure and function. The secondary, tertiary, and quaternary levels of protein structure involve the folding, arrangement, and interactions between amino acids, respectively.
21.
How many amino acid changes are required to truly alter the function of a protein? (See the sickle-cell example on p.84)
Correct Answer
A. 1
Explanation
A single amino acid change can truly alter the function of a protein. This is illustrated by the sickle-cell example on page 84, where a single amino acid substitution in the hemoglobin protein leads to the formation of abnormal sickle-shaped red blood cells and causes the disease. Thus, even a small change in the amino acid sequence can have a profound impact on the function of a protein.
22.
List 4 things that can cause a protein to become denatured.
23.
If a protein is denatured by heat or chemicals it can actually recover and go back to its functional shape once the heat or chemicals are removed.
Correct Answer
A. True
Explanation
When a protein is denatured by heat or chemicals, it means that its shape and structure have been altered. However, denaturation is usually reversible, meaning that the protein can regain its functional shape once the heat or chemicals are removed. This is because the primary structure of the protein, which is the sequence of amino acids, remains intact even after denaturation. Once the denaturing agent is removed, the protein can refold into its original shape through a process called renaturation. Therefore, the statement is true.
24.
Special proteins that help newly made polypeptides to fold into their 3-D shapes correctly are called ____________________.
Correct Answer
chaperonins
chaperonin
chaperone proteins
Explanation
Chaperonins, chaperonin, and chaperone proteins are all correct answers to the question. These special proteins assist in the folding process of newly synthesized polypeptides, ensuring they adopt their correct 3-D shapes. Chaperonins act as molecular chaperones, providing a protected environment for the folding process to occur. Chaperonin is a specific type of chaperonin protein, while chaperone proteins encompass a broader category of proteins that assist in protein folding.
25.
What happens if proteins are created with an incorrect shape?